Casing cutter



- Aug-19, 1930. w CHURCH 1,773,389 7 CASING CUTTER Filed March 22, 1927 I} o o a: [q a: /22 9: a:

Patented Aug. 19, 1939 1 UNITED STATES WALTER L. CHURCH, OF HOUSTON, TEXAS, ASSIGNOR"OF ONE-HALF TO W. L. PEARCE,-

PATEN OFFICE OF HARRIS COUNTY, TEXAS cnsme ou'r'rnn Application filed March 22, 1927.v seen No. name.

This invention relates to new and useful improvements in a casing cutter.

One object of the invention is to provide a cutter of the character described specially designed for cutting casing or pipe, stuck in a well bore, and such as cannot be pulled from the bore as a whole and must be cut into sections and removed, a section at a time.

Another object of the invention is to pro- 1 vide a cutter for casing or'pipe embodying a cutter body equipped with radially movable bits and including means normally holding said bits in withdrawn or inactive position and means operable by fluid pressure whereby said bitsmay be gradually forced outwardly into active position, or cutting relation with the pipe to be severed; and the in-' vention further comprehends means effective to indicate to the operator that the pipe has been severed.

With the above and other objects in view this invention has particular relation to certain novel features of constructiomoperation and arrangement of parts, an example of which is given in this specification and illustrated in the accompanying drawings, wherein I Figure 1 shows a vertical sectional view of the cutter.

Figure 2 shows a cross sectional view thereof, taken on the line22 of Figure 1, and

-Figure 3 shows a cross sectional View of one of the bit holders employed.

Referring now more particularly to the drawings, wherein like numerals of reference designate similar parts in each of the figures the numeral 1 designates the cutter body whose lower end is rounded off, or convex, as at 2, and which has an axial fluid passageway 3 extending from the upper to the lower end thereof. Connected to the upper end of the body 1 there is a cylinder l whose upper end is attached to the lower end of the operating tubular stem 5. There is a disc-like-anvided to admit water from the stem 5 into chor 6 closing the upper end of the cylinder 4' the cylinder and to exclude foreign matter. Mounted in suitable radial bearings 8 in the body 1 are the bit carriers 9, which are radially movable and which are held against turning by the keys 10, which work in the radial keyways 11 cut in the body. Mounted in the outerend of each carrier there is a bit 12 whose outer end is formed into a sharp cutting tooth which projects beyond the outer end of the carrier. The'bits are secured in the respective carriers by means of suitable set screws, as 13. The inner ends of the cutter 'ca'rriers are mitered, as shown in Figure 2, and beneath each carrier the body is provided with a verticalgroove 14- in which is located the flat spring 15 whose lower end is secured to the body and whose upper end works againsttheouter side of the pin '16 carried by the corresponding carrier to hold the carriers withdrawn inside the body'so that the bits will be in inactive position. Within the cylinder 4' there is a conventional'plunger 17 having small vertical fluid passageways 18 therethrough. A mandrel 19 has its upper end anchored to the plung'er 1 7 and its lower end is tapered and works between the mitered ends of the carriers 9. In the upper end of the passageway 3 there is an upwardly flared seat 20 and aboverthisseatthe mandrel '19 is reduced forming a tapering valve 21 conforming to the contour of and adapted to seat against the seat 20.

A coil spring 22 surrounds the mandrel and is interposed between the body 1 and the plunger 17.

In operation the cutter is ,letdown into the pipe to be cut'to the desired place, fluid, such as water, is then forced down through the stem 5 which acts against the plunger 17 and forces it downwardly and the tapered end of the mandrel l9 gradually forces the bit carriers and the bits outwardly into contact with the pipe to be cut. The cutter is rotated and the bits will gradually be forced into and will sever the pipe to be cut. WVhil-e the cutting operation is being carried on the water will pass on down through the passageways 18 and out through the passageway 3 thus relieving the pressure somewhat above the plunger 17 to permit the pump, supplying the pressure, to continue to operate but when the pipe to be cut has been severed the valve 21 will seat on and close the seat 20 and completely stop the circulation, thus increasing the work of the pump and eventually stop the same. The pump action will indicate to the operator that the plpe has been severed. The pressure being relieved above, the plunger and the mandrel.

carried thereby, Will move upwardly and springs 15 will withdraw the bits into inactive position and the cutter may be then withdrawn and the severed section of the pipe removed.

It is to be noted by an inspection of Figure 2 that some of the bits 12 are offset relative to the others. This arrangement is preferable so that the cut made by one bit will be made along one side only of the cut made. by the bit preceding it. This staggered, or offset arrangement of the bits will relieve the strain of the work on each bit giving a wider cut and preventing the chattering of the bits While at work. i

"What I claim is l. A pipe cutter including, in combination, a cutter body, outwardly movable. cutters carried by said body, means in the body through which said cutters may be forced outwardly into active, or cutting, position, means for moving said cutters inwardly, said cutters being arranged in difierent, but adjacent, working planes so as to make a common cut through the pipe to be severed.

2. A pipe cutter including, in combina: tion, a cutter body, radially movable cutters mountedtherein, some of said cutters being located to work in a different working plane from that of other of said cutters, said cutters being arranged adjacent so as to make a common cut through the pipe to be severed.

In testimony whereof I have signedsmy name to this specification.

WALTER L. CHURCH. 

